The activity of drawing is a mobile thing – a living process, something like a journey, whereas the finished drawing is when the journey has come to a halt; reached its destiny, completed its life. The finished drawing has become its own static memorial. We see the final drawing, but not the journey undertaken by the artist.
Paul Klee memorably called the process of drawing - ‘taking a line for a walk’.
 (This is a drawing I did when I was ill in bed with the flu).